System and method for adjusting separate devices concurrently

ABSTRACT

An apparatus for conditioning an electronic signal that includes a number of signal amplifiers sequentially arranged from a first amplifier to a final amplifier. There is also a microcontroller/microcomputer. A balance circuit is interposed between the first amplifier and the microcontroller/microcomputer, and a calibration step circuit is interposed between the microcontroller/microcomputer and a second amplifier. A digital to analog converter (DAC) is interposed between the microcontroller/microcomputer and each of the amplifiers.

STATEMENT OF GOVERNMENT INTEREST

[0001] The invention described herein may be manufactured and used by orfor the Government of the United States of America for governmentalpurposes without the payment of any royalties thereon or therefor.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to electronic signal amplificationsystems and more particularly to means for calibrating electronic signalamplification systems.

[0004] 2. Brief Description of the Prior Art

[0005] For various uses it is necessary to provide a means of convertinglow level voltage signals from transducers to voltage level signals. Insuch systems, a means of calibrating the amplifiers must be provided.

[0006] U.S. Pat. No. 4,510,454 to Sherman, for example, disclosesdigitally controlled calibration of amplifiers in which the devicerefers to a memory for the calibration specification.

[0007] U.S. Pat. No. 5,561,395 to Melton et al, discloses an amplifiercalibration system that is controlled automatically by a controller thathas the specification in storage.

[0008] U.S. Pat. No. 5,867,060 to Burkett, Jr. et al, discloses a powerdelivery system for amplifiers that refers to a memory. The memory is instorage and is addressed from a system controller.

SUMMARY OF THE INVENTION

[0009] The present invention comprises an apparatus for conditioning anelectronic signal comprising signal amplifying means; means forinputting a signal into each of the amplifying means; electronic controlmeans; balance means electronically interconnected between the controlmeans and the signal amplifying means; calibration means electronicallyinterconnected between the control means and the signal amplifyingmeans; and digital to analog converter (DAC) means electronicallyinterposed between the control means and the signal amplifying means.

[0010] Preferably there will be multiple individual card signalamplifiers, which in a preferred case may be twenty-one, but any numbercould be employed. The amplifiers do not use balance, calibration, orfinal gain stage potentiometers. The balance, calibration and final gaincontrol are all done with a microcontroller controlled digital to analogconverter (DAC). Two single DAC's which are a balance circuit and acalibration step circuit will control, respectively, the balance andcalibration steps for all amplifiers while an amp card level DAC willcontrol the final output gain. The microcontroller is the brain of theunit; allowing control, memory and interfacing to the amp box. A user,through the keypad interface, will be able to load particularcalibration values (scaling relations) where the values are stored inflash memory for future use. The calibration values translate thevoltage signal into appropriate engineering units. A technician will beable to press one button and all the channels will be zeroed, thecalibrations will be turned on and the final output stage gainautomatically set to the user level all within seconds, thus reducingthe setup time from an hour to mere seconds. Through a preferably 900MHz transmitter, a user will be able to do all the above remotely. Allof the previous levels can be read back from memory, which will allow afield engineer to judge whether a transducer is behaving correctly. Asimple data collection routine can be built into the microcontroller runtime software allowing a back up means for data collection to the datathat is sent real time to an instrumentation van. The data can betransmitted back to a remote location in real time provided the userstays within the limits of the baud transmission rate or the data can bedigitized, stored in memory and downloaded after an experiment through apreferably 900 MHz modem.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Other objects, features and advantages of the present inventionwill become apparent upon reference to the following description of thepreferred embodiments and to the drawing, wherein correspondingreference characters indicate corresponding parts in the drawing andwherein:

[0012]FIG. 1 is a schematic block diagram of a preferred embodiment ofthe amplifier system of the present invention;

[0013]FIG. 2 is a schematic diagram showing one particular preferredamplifier circuit, which may be used in the system shown in FIG. 1; and

[0014]FIG. 3 is a software flow chart used in the system shown in FIG.1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0015] Referring to FIG. 1 the system includes a plurality of amplifierssuch as signal amplifier 10 (Amp 1), signal amplifier 12 (Amp 2) andsignal amplifier 14 (Amp n). There is a signal input 16 to signalamplifier 10. There is a signal input 18 to signal amplifier 12, and asignal input 20 to signal amplifier 14. The system also includes amicrocontroller/microcomputer 22. There is also a balance circuit 24 anda calibration step circuit 26. Between the microcontroller/microcomputer22 and the balance circuit 24 there is an interconnection 28. Betweenthe microcontroller/microcomputer 22 and the calibration step circuit 26there is an interconnection 30. Between balance circuit 24 and signalamplifier 10 there is an interconnection 32. Between calibration stepcircuit 26 and amplifier 12 there is an interconnection 34. Betweensignal amplifier 10, signal amplifier 12 and signal amplifier 14 thereis an interconnection 36. Between signal amplifier 10 and signalamplifier 14 there is an interconnection 38. There is also a DAC 40,which is connected to signal amplifiers 10, 12 and 14 through DAC input41. The microcontroller/microcomputer 22 is connected to DAC 40 by input42. Digital controlled final output stage data is inputted frommicrocontroller/microcomputer 22 through line 41 to signal amplifier 14.The system also includes a 900 MHz modem 44, which is interconnected tothe microcontroller/microcomputer 22 by interconnection 46. There isalso a LCD display 48, which is interconnected tomicrocontroller/microcomputer 22 by interconnection 50. There is anumeric keypad 52, which is interconnected tomicrocontroller/microcomputer 22 by interconnection 54. There is alaptop computer interface 56, which is interconnected tomicrocontroller/microcomputer 22 by interconnection 58.

[0016] Referring to FIG. 2, a preferred circuit, which may be used inthe signal amplifiers 10, 12 and/or 14 is shown. This circuit includes apositive input signal line 60 and an negative input signal line 62 todifferential operational amplifier 64. This positive input signal line60 and negative input signal line 62 correspond respectively to lines16, 18, and/or 20 for signal amplifiers 10, 12 and 14 respectively. Thedifferential operational amplifier 64 is connected to summing junction66 which in turn is connected to inverting operational amplifier 68,which is connected by lines 70 and 72 to sample and hold device 74,which is connected by line 76 to digital control switch 78, which inputsto summing junction 66 through lines 80 and 82. There is a calibrationcircuit 84 which is interconnected to microcontroller/microcomputer 22by input line 86 and which is connected to the digital control switch 78through line 88. There is also a shift regulator 90 that is connected todigital control switch 78 through input lines 72 and to themicrocontroller/microcomputer 22 through interconnection 94. Line 96inputs to DAC 98, which produces final gain. DAC 98 is alsointerconnected to the microcontroller/microcomputer 22 throughinterconnection 100. Line 102 connects the DAC 98 to an invertingoperational amplifier 104 (Amp n) which also receives line 106 and hasoutput line 108. It will be understood that the inputs/outputs to themicrocontroller/microcomputer 22 at interconnections 94, 86 and 100correspond to interconnections 28, 30 and 32 in FIG. 1.

[0017] Referring to FIG. 3, in the software flowchart there is a poweron 110 followed by a print welcome message 112. There is a setup onswitch 114 followed by a setup routine for calibration and gain setup116. There is then a zero switch on 118 and a disable calibration outputto zero all functions 120. There is then a calibration switch on 124followed by an enable calibration on all channels 126. Next there is akeyboard input 128 followed by a trap keyboard input 130. Finally thereis a collected data set 132 followed by a data collection and setuproutine 134.

[0018] It will be appreciated that the above-described apparatusdiscloses means for quickly and efficiently calibrating amplificationsystems.

[0019] While the present invention has been described in connection withthe preferred embodiments of the various elements, it is to beunderstood that other similar embodiments may be used or modificationsand additions may be made to the present described embodiment forperforming the same function of the present invention without deviatingtherefrom. Therefore, the present invention should not be limited to anysingle embodiment, but rather construed in breadth and scope inaccordance with the recitation of the appended claims.

What is claimed is:
 1. A system for conditioning an electronic signalcomprising: signal amplifying means; means for inputting an electronicsignal into the amplifying means; electronic control means; balancemeans electronically interconnected between the control means and thesignal amplifying means; calibration means electronically interconnectedbetween the control means and the signal amplifying means; and digitalto analog converter means electronically interconnected between thecontrol means and the signal amplifying means.
 2. The system of claim 1wherein the signal amplifying means comprise a plurality of amplifiers.3. The system of claim 1 wherein the electronic control means is amicrocontroller/microcomputer.
 4. The system of claim 1 wherein thebalance means is a balance circuit.
 5. The system of claim 1 wherein thecalibration means is a calibration step circuit.
 6. The system of claim3 wherein the microcontroller/microcomputer is interconnected with amodem.
 7. The system of claim 3 wherein themicrocontroller/microcomputer is interconnected with an LCD display. 8.The system of claim 3 wherein the microcontroller/microcomputer has alaptop interface.
 9. The system of claim 2 wherein the amplifiers areinterconnected from Amp 1 to Amp 2 to Amp n such that Amp 1 is directlyconnected to Amp 2 and Amp n, Amp 2 is directly connect to Amp 1 and Amp2, and Amp n is directly connected to Amp 1 and Amp
 2. 10. The system ofclaim 9 wherein the balance means is interposed between the controlmeans and Amp
 1. 11. The system of claim 2 wherein the balance means isinterposed between the control means and one of the amplifiers.
 12. Thesystem of claim 10 wherein the calibration means is interposed betweenthe control means and Amp
 2. 13. The system of claim 11 wherein thebalance means is interposed between the control means and one of theamplifiers.
 14. The system of claim 12 wherein means are provided toinput a final output stage gain from the control means to Amp n.
 15. Thesystem of claim 13 wherein means are provided to input a final outputstage gain from the control means to one of the amplifiers.
 16. Thesystem of claim 14 wherein the DAC means is interposed between thecontrol means and Amp 1, Amp 2 and Amp n.
 17. The system of claim 15wherein the DAC means is interposed between the electronic control meansand each of said amplifiers.
 18. A system for conditioning an electronicsignal comprising: a first, second and third signal amplifier and meansfor inputting an electronic signal into each of said amplifiers;electronic control means; a balance circuit electronically interposedbetween the first amplifier and the electronic control means; acalibration step circuit electronically interposed between the secondamplifier and the electronic control means; a digital to analogconverter (DAC) electronically interposed between the electronic controlmeans and said first, second and third amplifier.
 19. The system ofclaim 18 wherein means are provided to electronically interconnect thefirst, second and third amplifiers.
 20. A system for conditioning anelectronic system comprising: a plurality of signal amplifierssequentially arranged from a first amplifier, Amp 1, to a finalamplifier, Amp n, wherein there is at least one amplifier, Amp 2,interposed between said amplifiers, Amp 1 and Amp n; a means forinputting an electronic signal to each of said amplifiers, Amp 1, Amp 2and Amp n; a microcontroller/microcomputer; a balance circuitinterconnected with said amplifier, Amp 1, and also interconnected withsaid microcontroller/microcomputer; a calibration step circuitinterconnected with said amplifier, Amp 2 and also interconnected withsaid microcontroller/microcomputer; and a digital to analog converter(DAC) interconnected with each of said amplifiers, Amp 1, Amp 2 and Ampn, and also interconnected with said microcontroller/microcomputer; andmeans for interconnecting said amplifier, Amp 1 with said amplifiers,Amp 2 and Amp n, and for interconnecting said amplifier, Amp 2, withsaid amplifier, Amp n.